/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.tracker.imports.programrule.engine;

import java.util.List;
import java.util.Optional;
import java.util.Set;
import org.hisp.dhis.cache.Cache;
import org.hisp.dhis.cache.CacheProvider;
import org.hisp.dhis.program.Program;
import org.hisp.dhis.programrule.ProgramRule;
import org.hisp.dhis.programrule.ProgramRuleActionType;
import org.hisp.dhis.programrule.ProgramRuleService;
import org.springframework.stereotype.Component;

@Component
public class ImplementableRuleService {
  private final ProgramRuleService programRuleService;
  private final Cache<Boolean> programHasRulesCache;

  public ImplementableRuleService(
      ProgramRuleService programRuleService, CacheProvider cacheProvider) {
    this.programRuleService = programRuleService;
    this.programHasRulesCache = cacheProvider.createProgramHasRulesCache();
  }

  protected List<ProgramRule> getProgramRulesByActionTypes(
      Program program, String programStageUid) {
    Set<ProgramRuleActionType> programRuleActionTypes =
        ProgramRuleActionType.SERVER_SUPPORTED_TYPES;
    if (programStageUid == null) {
      return programRuleService.getProgramRulesByActionTypes(program, programRuleActionTypes);
    } else {
      return programRuleService.getProgramRulesByActionTypes(
          program, programRuleActionTypes, programStageUid);
    }
  }

  public List<ProgramRule> getProgramRules(Program program, String programStageUid) {
    Optional<Boolean> optionalCacheValue = this.programHasRulesCache.get(program.getUid());

    if (optionalCacheValue.isPresent() && Boolean.FALSE.equals(optionalCacheValue.get())) {
      return List.of();
    }

    List<ProgramRule> programRulesByActionTypes =
        getProgramRulesByActionTypes(program, programStageUid);

    if (programStageUid == null) // To populate programHasRulesCache at
    // enrollment
    {
      this.programHasRulesCache.put(program.getUid(), !programRulesByActionTypes.isEmpty());

      // At enrollment, only those rules should be selected for execution
      // which are not associated with any ProgramStage.
      return programRulesByActionTypes.stream()
          .filter(rule -> rule.getProgramStage() == null)
          .toList();
    }

    return programRulesByActionTypes;
  }
}
